Cr-doped TiO2 thin films deposited by RF-sputtering

Abstract Cr-doped TiO 2 thin films with different band gaps were prepared. Higher Cr doping was beneficial to the formation of the rutile-TiO 2 phase over the anatase-TiO 2 phase. A 4.8% Cr-doped thin film indicated a band gap of 2.95 eV, which was lower than the band gap of the rutile-TiO 2 . Cr doping was accompanied by the formation of not only the rutile-TiO 2 phase but also the Cr 2 O 3 phase, lead to the degradation of the hydrophilicity. The TiO 2 thin films with the mixed phase were not desirable to improve the hydrophilicity.